Electric motor



No Model.) 4 Sheets--Sheet 1.

P. E. HBRDMAN. ELECTRIC MOTOR.

No. 551,633. Patented Dec. 17, 1895.

MTV/756656.'

(No Model.) 4 Sheets-Sheet 2.

F. E. HERDMAN.

ELECTRIC MOTOR.

No. 551,533. A Patented 1155. 17, 1895.

(No Model.) 4 Sheets-Sheet 3.

F. E. HERDMAN. ELECTRIC; MoToR.

frn/5656.' lire/from- AN DREW BJSRAHAM. FNDTOLITHO,WASHI N GTOPLD C.

(No Model.) 4 Sheets-Sheet 4.

F.A E. HERDMAN.

ELEGTRIG MOTOR.

No. 551,533.4 Patented D55. 17, 1895.

TIG', Q.

WCW @am UNITED STATES PATENT GEETCE.

FRANK E. IIERDMAN, OF IVINNETKA, ILLINOIS.

ELECTRIC MOTOR.

SPECIFICATION formingpart of Letters Patent No. 551,633, dated December 17, 1895.

Application filed August 6, 1894. Serial No. 519,572. (No model.)

To @ZZ whom t may concern:

Be it known that I, FRANK E. HERDMAN, a citizen of the United States, residing at Vinnetka, county of Cook, and State of Illinois, have invented a new and useful Improvement in Electric Motors, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form a part of this speciiication.

My invention has particular reference to certain improvements in electric motors whereby the strength of the iield can be varied at the will of the operator, thereby increasing or decreasing the speed of the motor, and thus give better control and greater efficiency in the consumption of the current by the operation of the electric motor.`

Iwill describe my improvement as adapted for use with the elevator; but I de not intend to limit myself to its use, as it can be used where the motor is used for purposes other than operating an elevator.

In the drawings, Figure 1 is a diagrammatical view showing path of current. Fig. 2 is a dia-grammatical view of modified form,show ing the path of the current. Fig. 3 is a diagrammatical view of another modified form, showing the path of the current. Fig. 4. is a front elevation of elevator apparatus with my invention applied. Fig. 5 is a modified form showing a part of the mechanism in different positions drawn to a larger scale.

Referring first to Figs. 1, 4, and 5, M is the motor on the shaft m. On this shaft is the brale-whecl m, provided with the strap brake m2. Connected to the shaft m is the worin N, which opera-tes the worin-wheel on the drum-shaftt, upon which shaft is also the operating-drum n2.

A is the rheostat-box in which is contained the motor controlling switch A, having the brushes a a. a2 a3.

X and Y are the wires leading from the source of current-supply, the wire being in electrical connection with the switch A.

B is the solenoid in electrical connection with the brushes c3 and a.

C are the resistances in electrical connection with brush a. D is an arm having the brush d, adapted te travel over said resistance.

d' is the axis of arm D and is in electrical connection with the armature of the motor,

the armature of the motor being also in electrical connection with the brush c2.

d3 is an arm, one end connected to the core of the solenoid B, the other end being connected to the dash-pot B. The main-line circuit goes directly to the iield of the motor.

E is a Contact in electrical connection with the wire Y from the source of current supply, and F are a series of contacts in electrical connection with the switch A. Under the arm D is a brush g of such size as to be in contact with contact E and contacts F. This brush g is attached to an arm G, (shown in detail, Fig. 5,) this arm being provided with the linger II extending upward on one side of the arm D. Connected to the arm G is the weight I, this weight being sufficient to move the arm G to the right when so desired. The contacts F are in electrical connection with additional coils to the held-magnets. As the arm D passes over the resistance-contacts C, the arm G also passes ever the contacts E and F by means of the action of the weight I, and when the arm D returns to the left, cutting the current out of the armature, by reason of said arm striking the linger Il. on the arm G, the arm G is also carried to the left. The extreme left position of this arm G places in circuit all oi' the additional coils to the field-magnet, and, consequently, at the moment of starting,the iields have their greatest strength. This strength of the fields be ing reduced as the arin passes to the right, as in its passage to the right it will cut out, one by one the extra coils from the circuit until it passes to the 4extreme right contact when all of the extra coils are cut out of cir cuit. In order that the position of the arm G may be controlled at the will of the operator, I attach to the arm G the bar J, provided with the slot j, in which slot works the guidepin k. At the end of this bar J are the flanges jg.

T is the operating-bar, which is connected te the switch A and is operated by the operator in the car by means of the lever t, and to this operating-bar is attached the bell-crank I., carrying at its end the roller 0, which, when the arin G is in its eXtreme left position, will be in contact with the iianged portien jg of the bar J. The weight I, tending to force the bar to the right, holds the bar IOO and roller in contact. As the operator moves the operating-bar T to the right or left, the bell-crank L is also moved an d, in consequen ce of' the roller O moving in a circle, it is carried to the right, and as it moves away from the flanged portion jg the weight I will cause the arm G to move, and thus the arm .I also moves until the flanged portion j? again is in contact with the roller O.

In starting up, the operator throws the bar suliicient to close the circuit through the solenoid B by permitting the arm D to travel over the resistance-contacts C and admit current to the armature of the motor. At the same time, the roller O having moved away from the fianged portion jg of the bar J, the weight I causes the arm G to move to the right, cutting out, one by one, the additional coils through the fields. The amount of this movement of the arm G- can be controlled by the operator by moving the operating-bar in either direction the desired amount, and by so doing he can regulate the strength ot the current, so as to have a strong or weak field, as desired, and thereby corresponding speed. By this construction the operator has the means of controlling the speed of the motor, and by it the speed of the device operated by the motor, at his option. wWhile he has this control of the fields during the operation, yet the motor must be started with the greatest strength upon the fields, and this cannot be reduced faster than the movement of the arm D will permit, for the finger II will prevent the arm G moving beyond the arm D, and thus lie cannot interfere with the arrangement of the fields for starting.

Fig. 2 shows a modification. In place of having several separate coils I have one extra winding, and reduce the field strength by means of the resistances IOO in the circuit to the extra winding, the greatest resistance being in the extra winding of the field, when the arm Gr is farthest to the right, and the operator, by moving the operating-bar T, can vary the current strength in the field, and by this, as in the prior description, regulate the speed of the motor.

In Fig. 3 I discard the use of extra coils, and regulate the current strength in the field, by including resistances in the circuit to the field-coil, and by regulating the position of the arm G, through which the current passes to the held, upon the resistance, I increase or decrease the current strength in the field, and thereby regulate the speed of the motor. The position of the arm G with relation to the arm D is the same as in Figs. l and 2.

I do not intend to limit myself tothe exact construction of mechanism hereinbefore described, except wherein the saine is specifically claimed.

Having now fully described my invention, what I claim, and desire to protect by Letters Patent, is-

1. The combination of a motor provided with field windin g, a source ot current supply,

electrical connection with the armature of the motor, resistance in said circuit, electrical connection with the field of the motor, a device adapted in its movement in one direction to decrease the amount of current in the field, and in the other direction to increase the current in the field, an arm for controlling the resistance in the armature circuit, the field device being moved in one direction by the armature regulating arm, and its movement in the other direction being limited by said arm, and means to move said held regulating device independent ot the movement ofi' the armature regulating arm.

2. In combination, an electric motor, a source ot current supply, direct electrical connection between the fields and current sup ply, extra coils upon the field magnets, contacts in electrical connection with one pole of the source of current supply, contacts in electrical connection with the other pole of cur rent supply and with extra coils, an arm adapt ed to pass over said contacts, bar connected to said arm provided with flanged ends, an operating bar and a bell-crank, one end connected to the operating bar, the other end being provided with a roller adapted to rest adjacent to said flange of said bar.

3. In combination an electric motor, a source of current supply, direct electrical connection between the fields and current source, extra coils upon the field magnets, contacts in electrical connection with one pole of the source of current supply, contacts in electrical connection with the other pole of current supply and with extra coils, a weighted arm adapted to pass over said contacts, an operating bar and intermediate connection between said weighted arm and said bar.

Li. In combination, an electric motor, a source of current supply, direct electrical connection between the fields and current source, extra coils upon the field magnets, contacts in electrical connection with one pole of the source of current supply, contacts in electrical connection with the other pole of current supply, and with extra coils, a weighted arm adapted to pass over said contacts, a bar con nected to said weighted arm provided with flanged ends, an operating bar and a bell crank, one end connected to the opcratin g bar, the other end being provided with a roller adapted to rest adjacent to said flange ofi' said bar.

5. The combination of a motor provided with field winding, a source of current supply, electrical connection with the armature ofz the niotor,resistance in said circuit, electrical connection with the field of the motor, a device adapted in its movement in one direction to decrease the amount of current in the field, and in the other direction to increase the current in the field, an arin for controlling the resistance in the armature circuit, the field device moving in one direction in the movement of the armature arm, and mea-ns to move said field regulating device independent of IOO IIO

the movement of the armature regulating arm.

6. The combination of a motor provided with field winding, a source of current supply, electrical connection with the armature of the motor, resistance in said circuit, electrical connection with the field oi the motor, a device adapted in its movement in one direction to decrease the amount of' current in the field, and in the other direction to increase the current in the field, an arm for controlling the resistance in the armature circuit, the field device moving in one direction in the movement of the armature regulating arm, and its movement in the other direction being limited by the movement of said arm, and means to move said field regulating device independent of the movement of the armature regulating arm.

7. The combination of a motor provided with field winding, a source of current supply, electrical connection with the armature of' the motor, resistance in said circuit, electrical connection with the field of the motor, a device adapted in its movement in one direction to decrease the amount of current in the field, and in the other direction to increase the current in the field, an arm for controlling` the resistance in the armature circuit, the field device being adapted to move in unison with the movement of the armature arm in either direction, and means to move said field regulating device independent of the movement of said armature regulating arm.

S, In combination, an electric motor, a source of current supply, electrical connection between the fields and current supply, an arm adapted in its movement in one direction to decrease the amount of current in the field and in the other direction to increase the current in the field, a bar connected to said arm provided with flanged ends, an operating-bar and a bell-crank, one end connected to the operating bar, the other end being provided with a roller adapted to rest adjacent to said fiange of said bar.

9. In combination, an electric motorft source of current supply, electrical connection between the fields and current source, an arm adapted in its movement in one direction to decrease the amount of current in the field and in the other direction to increase the current in the field, an operating bar and intermediate connection between said arm and said bar, mechanism independent of the operating bar to move said arm in the direction to decrease the current in the field.

lO. In combination, an electric motor, a source of current supply, electrical connection between the fields and current source, an arm adapted in its movement in one direction to decrease the amount of current in the field, and in the other direction to increase the current in the field, an operating bar, intermediate connection between said arm and said bar, and means independent of said operating bar to move said arm in both directions.

ll. In combination, an electric motor, a source of current supply, electrical connection between the fields and current source, a weighted arm adapted in its movement in one direction to decrease the amount of cur rent in the field, and in the other direction to increase the current in the field, a bar connected to said weighted arm provided with flanged ends, an operating bar and a belln crank one end connected to the operating bar, the other end being provided with a roller adapted to rest adjacent to said flange of' said bar.

In testimony of which invention I have hereunto set my hand.

' FRANK E. HERDMAN. iVitnesses W. W. DooLrrrLE,

HENRY E. TURNER. 

